CodeGenModule.cpp revision 468ec6c0266e48fccb26ce50d5b915c645bb3c7b
1//===--- CodeGenModule.cpp - Emit LLVM Code from ASTs for a Module --------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This coordinates the per-module state used while generating code. 11// 12//===----------------------------------------------------------------------===// 13 14#include "CodeGenModule.h" 15#include "CGDebugInfo.h" 16#include "CodeGenFunction.h" 17#include "CGCall.h" 18#include "CGObjCRuntime.h" 19#include "Mangle.h" 20#include "TargetInfo.h" 21#include "clang/CodeGen/CodeGenOptions.h" 22#include "clang/AST/ASTContext.h" 23#include "clang/AST/CharUnits.h" 24#include "clang/AST/DeclObjC.h" 25#include "clang/AST/DeclCXX.h" 26#include "clang/AST/RecordLayout.h" 27#include "clang/Basic/Builtins.h" 28#include "clang/Basic/Diagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31#include "clang/Basic/ConvertUTF.h" 32#include "llvm/CallingConv.h" 33#include "llvm/Module.h" 34#include "llvm/Intrinsics.h" 35#include "llvm/LLVMContext.h" 36#include "llvm/Target/TargetData.h" 37#include "llvm/Support/ErrorHandling.h" 38using namespace clang; 39using namespace CodeGen; 40 41 42CodeGenModule::CodeGenModule(ASTContext &C, const CodeGenOptions &CGO, 43 llvm::Module &M, const llvm::TargetData &TD, 44 Diagnostic &diags) 45 : BlockModule(C, M, TD, Types, *this), Context(C), 46 Features(C.getLangOptions()), CodeGenOpts(CGO), TheModule(M), 47 TheTargetData(TD), TheTargetCodeGenInfo(0), Diags(diags), 48 Types(C, M, TD, getTargetCodeGenInfo().getABIInfo()), 49 MangleCtx(C), VtableInfo(*this), Runtime(0), 50 MemCpyFn(0), MemMoveFn(0), MemSetFn(0), CFConstantStringClassRef(0), 51 VMContext(M.getContext()) { 52 53 if (!Features.ObjC1) 54 Runtime = 0; 55 else if (!Features.NeXTRuntime) 56 Runtime = CreateGNUObjCRuntime(*this); 57 else if (Features.ObjCNonFragileABI) 58 Runtime = CreateMacNonFragileABIObjCRuntime(*this); 59 else 60 Runtime = CreateMacObjCRuntime(*this); 61 62 // If debug info generation is enabled, create the CGDebugInfo object. 63 DebugInfo = CodeGenOpts.DebugInfo ? new CGDebugInfo(*this) : 0; 64} 65 66CodeGenModule::~CodeGenModule() { 67 delete Runtime; 68 delete DebugInfo; 69} 70 71void CodeGenModule::createObjCRuntime() { 72 if (!Features.NeXTRuntime) 73 Runtime = CreateGNUObjCRuntime(*this); 74 else if (Features.ObjCNonFragileABI) 75 Runtime = CreateMacNonFragileABIObjCRuntime(*this); 76 else 77 Runtime = CreateMacObjCRuntime(*this); 78} 79 80void CodeGenModule::Release() { 81 EmitDeferred(); 82 EmitCXXGlobalInitFunc(); 83 if (Runtime) 84 if (llvm::Function *ObjCInitFunction = Runtime->ModuleInitFunction()) 85 AddGlobalCtor(ObjCInitFunction); 86 EmitCtorList(GlobalCtors, "llvm.global_ctors"); 87 EmitCtorList(GlobalDtors, "llvm.global_dtors"); 88 EmitAnnotations(); 89 EmitLLVMUsed(); 90} 91 92/// ErrorUnsupported - Print out an error that codegen doesn't support the 93/// specified stmt yet. 94void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type, 95 bool OmitOnError) { 96 if (OmitOnError && getDiags().hasErrorOccurred()) 97 return; 98 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error, 99 "cannot compile this %0 yet"); 100 std::string Msg = Type; 101 getDiags().Report(Context.getFullLoc(S->getLocStart()), DiagID) 102 << Msg << S->getSourceRange(); 103} 104 105/// ErrorUnsupported - Print out an error that codegen doesn't support the 106/// specified decl yet. 107void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type, 108 bool OmitOnError) { 109 if (OmitOnError && getDiags().hasErrorOccurred()) 110 return; 111 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error, 112 "cannot compile this %0 yet"); 113 std::string Msg = Type; 114 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg; 115} 116 117LangOptions::VisibilityMode 118CodeGenModule::getDeclVisibilityMode(const Decl *D) const { 119 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 120 if (VD->getStorageClass() == VarDecl::PrivateExtern) 121 return LangOptions::Hidden; 122 123 if (const VisibilityAttr *attr = D->getAttr<VisibilityAttr>()) { 124 switch (attr->getVisibility()) { 125 default: assert(0 && "Unknown visibility!"); 126 case VisibilityAttr::DefaultVisibility: 127 return LangOptions::Default; 128 case VisibilityAttr::HiddenVisibility: 129 return LangOptions::Hidden; 130 case VisibilityAttr::ProtectedVisibility: 131 return LangOptions::Protected; 132 } 133 } 134 135 // This decl should have the same visibility as its parent. 136 if (const DeclContext *DC = D->getDeclContext()) 137 return getDeclVisibilityMode(cast<Decl>(DC)); 138 139 return getLangOptions().getVisibilityMode(); 140} 141 142void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV, 143 const Decl *D) const { 144 // Internal definitions always have default visibility. 145 if (GV->hasLocalLinkage()) { 146 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 147 return; 148 } 149 150 switch (getDeclVisibilityMode(D)) { 151 default: assert(0 && "Unknown visibility!"); 152 case LangOptions::Default: 153 return GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 154 case LangOptions::Hidden: 155 return GV->setVisibility(llvm::GlobalValue::HiddenVisibility); 156 case LangOptions::Protected: 157 return GV->setVisibility(llvm::GlobalValue::ProtectedVisibility); 158 } 159} 160 161const char *CodeGenModule::getMangledName(const GlobalDecl &GD) { 162 const NamedDecl *ND = cast<NamedDecl>(GD.getDecl()); 163 164 if (const CXXConstructorDecl *D = dyn_cast<CXXConstructorDecl>(ND)) 165 return getMangledCXXCtorName(D, GD.getCtorType()); 166 if (const CXXDestructorDecl *D = dyn_cast<CXXDestructorDecl>(ND)) 167 return getMangledCXXDtorName(D, GD.getDtorType()); 168 169 return getMangledName(ND); 170} 171 172/// \brief Retrieves the mangled name for the given declaration. 173/// 174/// If the given declaration requires a mangled name, returns an 175/// const char* containing the mangled name. Otherwise, returns 176/// the unmangled name. 177/// 178const char *CodeGenModule::getMangledName(const NamedDecl *ND) { 179 if (!getMangleContext().shouldMangleDeclName(ND)) { 180 assert(ND->getIdentifier() && "Attempt to mangle unnamed decl."); 181 return ND->getNameAsCString(); 182 } 183 184 llvm::SmallString<256> Name; 185 getMangleContext().mangleName(ND, Name); 186 Name += '\0'; 187 return UniqueMangledName(Name.begin(), Name.end()); 188} 189 190const char *CodeGenModule::UniqueMangledName(const char *NameStart, 191 const char *NameEnd) { 192 assert(*(NameEnd - 1) == '\0' && "Mangled name must be null terminated!"); 193 194 return MangledNames.GetOrCreateValue(NameStart, NameEnd).getKeyData(); 195} 196 197/// AddGlobalCtor - Add a function to the list that will be called before 198/// main() runs. 199void CodeGenModule::AddGlobalCtor(llvm::Function * Ctor, int Priority) { 200 // FIXME: Type coercion of void()* types. 201 GlobalCtors.push_back(std::make_pair(Ctor, Priority)); 202} 203 204/// AddGlobalDtor - Add a function to the list that will be called 205/// when the module is unloaded. 206void CodeGenModule::AddGlobalDtor(llvm::Function * Dtor, int Priority) { 207 // FIXME: Type coercion of void()* types. 208 GlobalDtors.push_back(std::make_pair(Dtor, Priority)); 209} 210 211void CodeGenModule::EmitCtorList(const CtorList &Fns, const char *GlobalName) { 212 // Ctor function type is void()*. 213 llvm::FunctionType* CtorFTy = 214 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), 215 std::vector<const llvm::Type*>(), 216 false); 217 llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy); 218 219 // Get the type of a ctor entry, { i32, void ()* }. 220 llvm::StructType* CtorStructTy = 221 llvm::StructType::get(VMContext, llvm::Type::getInt32Ty(VMContext), 222 llvm::PointerType::getUnqual(CtorFTy), NULL); 223 224 // Construct the constructor and destructor arrays. 225 std::vector<llvm::Constant*> Ctors; 226 for (CtorList::const_iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 227 std::vector<llvm::Constant*> S; 228 S.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 229 I->second, false)); 230 S.push_back(llvm::ConstantExpr::getBitCast(I->first, CtorPFTy)); 231 Ctors.push_back(llvm::ConstantStruct::get(CtorStructTy, S)); 232 } 233 234 if (!Ctors.empty()) { 235 llvm::ArrayType *AT = llvm::ArrayType::get(CtorStructTy, Ctors.size()); 236 new llvm::GlobalVariable(TheModule, AT, false, 237 llvm::GlobalValue::AppendingLinkage, 238 llvm::ConstantArray::get(AT, Ctors), 239 GlobalName); 240 } 241} 242 243void CodeGenModule::EmitAnnotations() { 244 if (Annotations.empty()) 245 return; 246 247 // Create a new global variable for the ConstantStruct in the Module. 248 llvm::Constant *Array = 249 llvm::ConstantArray::get(llvm::ArrayType::get(Annotations[0]->getType(), 250 Annotations.size()), 251 Annotations); 252 llvm::GlobalValue *gv = 253 new llvm::GlobalVariable(TheModule, Array->getType(), false, 254 llvm::GlobalValue::AppendingLinkage, Array, 255 "llvm.global.annotations"); 256 gv->setSection("llvm.metadata"); 257} 258 259static CodeGenModule::GVALinkage 260GetLinkageForFunction(ASTContext &Context, const FunctionDecl *FD, 261 const LangOptions &Features) { 262 CodeGenModule::GVALinkage External = CodeGenModule::GVA_StrongExternal; 263 264 Linkage L = FD->getLinkage(); 265 if (L == ExternalLinkage && Context.getLangOptions().CPlusPlus && 266 FD->getType()->getLinkage() == UniqueExternalLinkage) 267 L = UniqueExternalLinkage; 268 269 switch (L) { 270 case NoLinkage: 271 case InternalLinkage: 272 case UniqueExternalLinkage: 273 return CodeGenModule::GVA_Internal; 274 275 case ExternalLinkage: 276 switch (FD->getTemplateSpecializationKind()) { 277 case TSK_Undeclared: 278 case TSK_ExplicitSpecialization: 279 External = CodeGenModule::GVA_StrongExternal; 280 break; 281 282 case TSK_ExplicitInstantiationDefinition: 283 // FIXME: explicit instantiation definitions should use weak linkage 284 return CodeGenModule::GVA_StrongExternal; 285 286 case TSK_ExplicitInstantiationDeclaration: 287 case TSK_ImplicitInstantiation: 288 External = CodeGenModule::GVA_TemplateInstantiation; 289 break; 290 } 291 } 292 293 if (!FD->isInlined()) 294 return External; 295 296 if (!Features.CPlusPlus || FD->hasAttr<GNUInlineAttr>()) { 297 // GNU or C99 inline semantics. Determine whether this symbol should be 298 // externally visible. 299 if (FD->isInlineDefinitionExternallyVisible()) 300 return External; 301 302 // C99 inline semantics, where the symbol is not externally visible. 303 return CodeGenModule::GVA_C99Inline; 304 } 305 306 // C++0x [temp.explicit]p9: 307 // [ Note: The intent is that an inline function that is the subject of 308 // an explicit instantiation declaration will still be implicitly 309 // instantiated when used so that the body can be considered for 310 // inlining, but that no out-of-line copy of the inline function would be 311 // generated in the translation unit. -- end note ] 312 if (FD->getTemplateSpecializationKind() 313 == TSK_ExplicitInstantiationDeclaration) 314 return CodeGenModule::GVA_C99Inline; 315 316 return CodeGenModule::GVA_CXXInline; 317} 318 319llvm::GlobalValue::LinkageTypes 320CodeGenModule::getFunctionLinkage(const FunctionDecl *D) { 321 GVALinkage Linkage = GetLinkageForFunction(getContext(), D, Features); 322 323 if (Linkage == GVA_Internal) { 324 return llvm::Function::InternalLinkage; 325 } else if (D->hasAttr<DLLExportAttr>()) { 326 return llvm::Function::DLLExportLinkage; 327 } else if (D->hasAttr<WeakAttr>()) { 328 return llvm::Function::WeakAnyLinkage; 329 } else if (Linkage == GVA_C99Inline) { 330 // In C99 mode, 'inline' functions are guaranteed to have a strong 331 // definition somewhere else, so we can use available_externally linkage. 332 return llvm::Function::AvailableExternallyLinkage; 333 } else if (Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation) { 334 // In C++, the compiler has to emit a definition in every translation unit 335 // that references the function. We should use linkonce_odr because 336 // a) if all references in this translation unit are optimized away, we 337 // don't need to codegen it. b) if the function persists, it needs to be 338 // merged with other definitions. c) C++ has the ODR, so we know the 339 // definition is dependable. 340 return llvm::Function::LinkOnceODRLinkage; 341 } else { 342 assert(Linkage == GVA_StrongExternal); 343 // Otherwise, we have strong external linkage. 344 return llvm::Function::ExternalLinkage; 345 } 346} 347 348 349/// SetFunctionDefinitionAttributes - Set attributes for a global. 350/// 351/// FIXME: This is currently only done for aliases and functions, but not for 352/// variables (these details are set in EmitGlobalVarDefinition for variables). 353void CodeGenModule::SetFunctionDefinitionAttributes(const FunctionDecl *D, 354 llvm::GlobalValue *GV) { 355 GV->setLinkage(getFunctionLinkage(D)); 356 SetCommonAttributes(D, GV); 357} 358 359void CodeGenModule::SetLLVMFunctionAttributes(const Decl *D, 360 const CGFunctionInfo &Info, 361 llvm::Function *F) { 362 unsigned CallingConv; 363 AttributeListType AttributeList; 364 ConstructAttributeList(Info, D, AttributeList, CallingConv); 365 F->setAttributes(llvm::AttrListPtr::get(AttributeList.begin(), 366 AttributeList.size())); 367 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv)); 368} 369 370void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D, 371 llvm::Function *F) { 372 if (!Features.Exceptions && !Features.ObjCNonFragileABI) 373 F->addFnAttr(llvm::Attribute::NoUnwind); 374 375 if (D->hasAttr<AlwaysInlineAttr>()) 376 F->addFnAttr(llvm::Attribute::AlwaysInline); 377 378 if (D->hasAttr<NoInlineAttr>()) 379 F->addFnAttr(llvm::Attribute::NoInline); 380 381 if (Features.getStackProtectorMode() == LangOptions::SSPOn) 382 F->addFnAttr(llvm::Attribute::StackProtect); 383 else if (Features.getStackProtectorMode() == LangOptions::SSPReq) 384 F->addFnAttr(llvm::Attribute::StackProtectReq); 385 386 if (const AlignedAttr *AA = D->getAttr<AlignedAttr>()) { 387 unsigned width = Context.Target.getCharWidth(); 388 F->setAlignment(AA->getAlignment() / width); 389 while ((AA = AA->getNext<AlignedAttr>())) 390 F->setAlignment(std::max(F->getAlignment(), AA->getAlignment() / width)); 391 } 392 // C++ ABI requires 2-byte alignment for member functions. 393 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D)) 394 F->setAlignment(2); 395} 396 397void CodeGenModule::SetCommonAttributes(const Decl *D, 398 llvm::GlobalValue *GV) { 399 setGlobalVisibility(GV, D); 400 401 if (D->hasAttr<UsedAttr>()) 402 AddUsedGlobal(GV); 403 404 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) 405 GV->setSection(SA->getName()); 406 407 getTargetCodeGenInfo().SetTargetAttributes(D, GV, *this); 408} 409 410void CodeGenModule::SetInternalFunctionAttributes(const Decl *D, 411 llvm::Function *F, 412 const CGFunctionInfo &FI) { 413 SetLLVMFunctionAttributes(D, FI, F); 414 SetLLVMFunctionAttributesForDefinition(D, F); 415 416 F->setLinkage(llvm::Function::InternalLinkage); 417 418 SetCommonAttributes(D, F); 419} 420 421void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, 422 llvm::Function *F, 423 bool IsIncompleteFunction) { 424 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 425 426 if (!IsIncompleteFunction) 427 SetLLVMFunctionAttributes(FD, getTypes().getFunctionInfo(GD), F); 428 429 // Only a few attributes are set on declarations; these may later be 430 // overridden by a definition. 431 432 if (FD->hasAttr<DLLImportAttr>()) { 433 F->setLinkage(llvm::Function::DLLImportLinkage); 434 } else if (FD->hasAttr<WeakAttr>() || 435 FD->hasAttr<WeakImportAttr>()) { 436 // "extern_weak" is overloaded in LLVM; we probably should have 437 // separate linkage types for this. 438 F->setLinkage(llvm::Function::ExternalWeakLinkage); 439 } else { 440 F->setLinkage(llvm::Function::ExternalLinkage); 441 } 442 443 if (const SectionAttr *SA = FD->getAttr<SectionAttr>()) 444 F->setSection(SA->getName()); 445} 446 447void CodeGenModule::AddUsedGlobal(llvm::GlobalValue *GV) { 448 assert(!GV->isDeclaration() && 449 "Only globals with definition can force usage."); 450 LLVMUsed.push_back(GV); 451} 452 453void CodeGenModule::EmitLLVMUsed() { 454 // Don't create llvm.used if there is no need. 455 if (LLVMUsed.empty()) 456 return; 457 458 const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext); 459 460 // Convert LLVMUsed to what ConstantArray needs. 461 std::vector<llvm::Constant*> UsedArray; 462 UsedArray.resize(LLVMUsed.size()); 463 for (unsigned i = 0, e = LLVMUsed.size(); i != e; ++i) { 464 UsedArray[i] = 465 llvm::ConstantExpr::getBitCast(cast<llvm::Constant>(&*LLVMUsed[i]), 466 i8PTy); 467 } 468 469 if (UsedArray.empty()) 470 return; 471 llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, UsedArray.size()); 472 473 llvm::GlobalVariable *GV = 474 new llvm::GlobalVariable(getModule(), ATy, false, 475 llvm::GlobalValue::AppendingLinkage, 476 llvm::ConstantArray::get(ATy, UsedArray), 477 "llvm.used"); 478 479 GV->setSection("llvm.metadata"); 480} 481 482void CodeGenModule::EmitDeferred() { 483 // Emit code for any potentially referenced deferred decls. Since a 484 // previously unused static decl may become used during the generation of code 485 // for a static function, iterate until no changes are made. 486 while (!DeferredDeclsToEmit.empty()) { 487 GlobalDecl D = DeferredDeclsToEmit.back(); 488 DeferredDeclsToEmit.pop_back(); 489 490 // The mangled name for the decl must have been emitted in GlobalDeclMap. 491 // Look it up to see if it was defined with a stronger definition (e.g. an 492 // extern inline function with a strong function redefinition). If so, 493 // just ignore the deferred decl. 494 llvm::GlobalValue *CGRef = GlobalDeclMap[getMangledName(D)]; 495 assert(CGRef && "Deferred decl wasn't referenced?"); 496 497 if (!CGRef->isDeclaration()) 498 continue; 499 500 // Otherwise, emit the definition and move on to the next one. 501 EmitGlobalDefinition(D); 502 } 503} 504 505/// EmitAnnotateAttr - Generate the llvm::ConstantStruct which contains the 506/// annotation information for a given GlobalValue. The annotation struct is 507/// {i8 *, i8 *, i8 *, i32}. The first field is a constant expression, the 508/// GlobalValue being annotated. The second field is the constant string 509/// created from the AnnotateAttr's annotation. The third field is a constant 510/// string containing the name of the translation unit. The fourth field is 511/// the line number in the file of the annotated value declaration. 512/// 513/// FIXME: this does not unique the annotation string constants, as llvm-gcc 514/// appears to. 515/// 516llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV, 517 const AnnotateAttr *AA, 518 unsigned LineNo) { 519 llvm::Module *M = &getModule(); 520 521 // get [N x i8] constants for the annotation string, and the filename string 522 // which are the 2nd and 3rd elements of the global annotation structure. 523 const llvm::Type *SBP = llvm::Type::getInt8PtrTy(VMContext); 524 llvm::Constant *anno = llvm::ConstantArray::get(VMContext, 525 AA->getAnnotation(), true); 526 llvm::Constant *unit = llvm::ConstantArray::get(VMContext, 527 M->getModuleIdentifier(), 528 true); 529 530 // Get the two global values corresponding to the ConstantArrays we just 531 // created to hold the bytes of the strings. 532 llvm::GlobalValue *annoGV = 533 new llvm::GlobalVariable(*M, anno->getType(), false, 534 llvm::GlobalValue::PrivateLinkage, anno, 535 GV->getName()); 536 // translation unit name string, emitted into the llvm.metadata section. 537 llvm::GlobalValue *unitGV = 538 new llvm::GlobalVariable(*M, unit->getType(), false, 539 llvm::GlobalValue::PrivateLinkage, unit, 540 ".str"); 541 542 // Create the ConstantStruct for the global annotation. 543 llvm::Constant *Fields[4] = { 544 llvm::ConstantExpr::getBitCast(GV, SBP), 545 llvm::ConstantExpr::getBitCast(annoGV, SBP), 546 llvm::ConstantExpr::getBitCast(unitGV, SBP), 547 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), LineNo) 548 }; 549 return llvm::ConstantStruct::get(VMContext, Fields, 4, false); 550} 551 552bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) { 553 // Never defer when EmitAllDecls is specified or the decl has 554 // attribute used. 555 if (Features.EmitAllDecls || Global->hasAttr<UsedAttr>()) 556 return false; 557 558 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Global)) { 559 // Constructors and destructors should never be deferred. 560 if (FD->hasAttr<ConstructorAttr>() || 561 FD->hasAttr<DestructorAttr>()) 562 return false; 563 564 // The key function for a class must never be deferred. 565 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Global)) { 566 const CXXRecordDecl *RD = MD->getParent(); 567 if (MD->isOutOfLine() && RD->isDynamicClass()) { 568 const CXXMethodDecl *KeyFunction = getContext().getKeyFunction(RD); 569 if (KeyFunction && 570 KeyFunction->getCanonicalDecl() == MD->getCanonicalDecl()) 571 return false; 572 } 573 } 574 575 GVALinkage Linkage = GetLinkageForFunction(getContext(), FD, Features); 576 577 // static, static inline, always_inline, and extern inline functions can 578 // always be deferred. Normal inline functions can be deferred in C99/C++. 579 if (Linkage == GVA_Internal || Linkage == GVA_C99Inline || 580 Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation) 581 return true; 582 return false; 583 } 584 585 const VarDecl *VD = cast<VarDecl>(Global); 586 assert(VD->isFileVarDecl() && "Invalid decl"); 587 588 // We never want to defer structs that have non-trivial constructors or 589 // destructors. 590 591 // FIXME: Handle references. 592 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 593 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 594 if (!RD->hasTrivialConstructor() || !RD->hasTrivialDestructor()) 595 return false; 596 } 597 } 598 599 // Static data may be deferred, but out-of-line static data members 600 // cannot be. 601 Linkage L = VD->getLinkage(); 602 if (L == ExternalLinkage && getContext().getLangOptions().CPlusPlus && 603 VD->getType()->getLinkage() == UniqueExternalLinkage) 604 L = UniqueExternalLinkage; 605 606 switch (L) { 607 case NoLinkage: 608 case InternalLinkage: 609 case UniqueExternalLinkage: 610 // Initializer has side effects? 611 if (VD->getInit() && VD->getInit()->HasSideEffects(Context)) 612 return false; 613 return !(VD->isStaticDataMember() && VD->isOutOfLine()); 614 615 case ExternalLinkage: 616 break; 617 } 618 619 return false; 620} 621 622void CodeGenModule::EmitGlobal(GlobalDecl GD) { 623 const ValueDecl *Global = cast<ValueDecl>(GD.getDecl()); 624 625 // If this is an alias definition (which otherwise looks like a declaration) 626 // emit it now. 627 if (Global->hasAttr<AliasAttr>()) 628 return EmitAliasDefinition(Global); 629 630 // Ignore declarations, they will be emitted on their first use. 631 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Global)) { 632 // Forward declarations are emitted lazily on first use. 633 if (!FD->isThisDeclarationADefinition()) 634 return; 635 } else { 636 const VarDecl *VD = cast<VarDecl>(Global); 637 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global."); 638 639 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) 640 return; 641 } 642 643 // Defer code generation when possible if this is a static definition, inline 644 // function etc. These we only want to emit if they are used. 645 if (MayDeferGeneration(Global)) { 646 // If the value has already been used, add it directly to the 647 // DeferredDeclsToEmit list. 648 const char *MangledName = getMangledName(GD); 649 if (GlobalDeclMap.count(MangledName)) 650 DeferredDeclsToEmit.push_back(GD); 651 else { 652 // Otherwise, remember that we saw a deferred decl with this name. The 653 // first use of the mangled name will cause it to move into 654 // DeferredDeclsToEmit. 655 DeferredDecls[MangledName] = GD; 656 } 657 return; 658 } 659 660 // Otherwise emit the definition. 661 EmitGlobalDefinition(GD); 662} 663 664void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD) { 665 const ValueDecl *D = cast<ValueDecl>(GD.getDecl()); 666 667 PrettyStackTraceDecl CrashInfo((ValueDecl *)D, D->getLocation(), 668 Context.getSourceManager(), 669 "Generating code for declaration"); 670 671 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 672 getVtableInfo().MaybeEmitVtable(GD); 673 if (MD->isVirtual() && MD->isOutOfLine() && 674 (!isa<CXXDestructorDecl>(D) || GD.getDtorType() != Dtor_Base)) { 675 if (isa<CXXDestructorDecl>(D)) { 676 GlobalDecl CanonGD(cast<CXXDestructorDecl>(D->getCanonicalDecl()), 677 GD.getDtorType()); 678 BuildThunksForVirtual(CanonGD); 679 } else { 680 BuildThunksForVirtual(MD->getCanonicalDecl()); 681 } 682 } 683 } 684 685 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 686 EmitCXXConstructor(CD, GD.getCtorType()); 687 else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(D)) 688 EmitCXXDestructor(DD, GD.getDtorType()); 689 else if (isa<FunctionDecl>(D)) 690 EmitGlobalFunctionDefinition(GD); 691 else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 692 EmitGlobalVarDefinition(VD); 693 else { 694 assert(0 && "Invalid argument to EmitGlobalDefinition()"); 695 } 696} 697 698/// GetOrCreateLLVMFunction - If the specified mangled name is not in the 699/// module, create and return an llvm Function with the specified type. If there 700/// is something in the module with the specified name, return it potentially 701/// bitcasted to the right type. 702/// 703/// If D is non-null, it specifies a decl that correspond to this. This is used 704/// to set the attributes on the function when it is first created. 705llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(const char *MangledName, 706 const llvm::Type *Ty, 707 GlobalDecl D) { 708 // Lookup the entry, lazily creating it if necessary. 709 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 710 if (Entry) { 711 if (Entry->getType()->getElementType() == Ty) 712 return Entry; 713 714 // Make sure the result is of the correct type. 715 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); 716 return llvm::ConstantExpr::getBitCast(Entry, PTy); 717 } 718 719 // This function doesn't have a complete type (for example, the return 720 // type is an incomplete struct). Use a fake type instead, and make 721 // sure not to try to set attributes. 722 bool IsIncompleteFunction = false; 723 if (!isa<llvm::FunctionType>(Ty)) { 724 Ty = llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), 725 std::vector<const llvm::Type*>(), false); 726 IsIncompleteFunction = true; 727 } 728 llvm::Function *F = llvm::Function::Create(cast<llvm::FunctionType>(Ty), 729 llvm::Function::ExternalLinkage, 730 "", &getModule()); 731 F->setName(MangledName); 732 if (D.getDecl()) 733 SetFunctionAttributes(D, F, IsIncompleteFunction); 734 Entry = F; 735 736 // This is the first use or definition of a mangled name. If there is a 737 // deferred decl with this name, remember that we need to emit it at the end 738 // of the file. 739 llvm::DenseMap<const char*, GlobalDecl>::iterator DDI = 740 DeferredDecls.find(MangledName); 741 if (DDI != DeferredDecls.end()) { 742 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 743 // list, and remove it from DeferredDecls (since we don't need it anymore). 744 DeferredDeclsToEmit.push_back(DDI->second); 745 DeferredDecls.erase(DDI); 746 } else if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D.getDecl())) { 747 // If this the first reference to a C++ inline function in a class, queue up 748 // the deferred function body for emission. These are not seen as 749 // top-level declarations. 750 if (FD->isThisDeclarationADefinition() && MayDeferGeneration(FD)) 751 DeferredDeclsToEmit.push_back(D); 752 // A called constructor which has no definition or declaration need be 753 // synthesized. 754 else if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) { 755 if (CD->isImplicit()) { 756 assert (CD->isUsed()); 757 DeferredDeclsToEmit.push_back(D); 758 } 759 } else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(FD)) { 760 if (DD->isImplicit()) { 761 assert (DD->isUsed()); 762 DeferredDeclsToEmit.push_back(D); 763 } 764 } else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 765 if (MD->isCopyAssignment() && MD->isImplicit()) { 766 assert (MD->isUsed()); 767 DeferredDeclsToEmit.push_back(D); 768 } 769 } 770 } 771 772 return F; 773} 774 775/// GetAddrOfFunction - Return the address of the given function. If Ty is 776/// non-null, then this function will use the specified type if it has to 777/// create it (this occurs when we see a definition of the function). 778llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD, 779 const llvm::Type *Ty) { 780 // If there was no specific requested type, just convert it now. 781 if (!Ty) 782 Ty = getTypes().ConvertType(cast<ValueDecl>(GD.getDecl())->getType()); 783 return GetOrCreateLLVMFunction(getMangledName(GD), Ty, GD); 784} 785 786/// CreateRuntimeFunction - Create a new runtime function with the specified 787/// type and name. 788llvm::Constant * 789CodeGenModule::CreateRuntimeFunction(const llvm::FunctionType *FTy, 790 const char *Name) { 791 // Convert Name to be a uniqued string from the IdentifierInfo table. 792 Name = getContext().Idents.get(Name).getNameStart(); 793 return GetOrCreateLLVMFunction(Name, FTy, GlobalDecl()); 794} 795 796static bool DeclIsConstantGlobal(ASTContext &Context, const VarDecl *D) { 797 if (!D->getType().isConstant(Context) && !D->getType()->isReferenceType()) 798 return false; 799 if (Context.getLangOptions().CPlusPlus && 800 Context.getBaseElementType(D->getType())->getAs<RecordType>()) { 801 // FIXME: We should do something fancier here! 802 return false; 803 } 804 return true; 805} 806 807/// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 808/// create and return an llvm GlobalVariable with the specified type. If there 809/// is something in the module with the specified name, return it potentially 810/// bitcasted to the right type. 811/// 812/// If D is non-null, it specifies a decl that correspond to this. This is used 813/// to set the attributes on the global when it is first created. 814llvm::Constant *CodeGenModule::GetOrCreateLLVMGlobal(const char *MangledName, 815 const llvm::PointerType*Ty, 816 const VarDecl *D) { 817 // Lookup the entry, lazily creating it if necessary. 818 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 819 if (Entry) { 820 if (Entry->getType() == Ty) 821 return Entry; 822 823 // Make sure the result is of the correct type. 824 return llvm::ConstantExpr::getBitCast(Entry, Ty); 825 } 826 827 // This is the first use or definition of a mangled name. If there is a 828 // deferred decl with this name, remember that we need to emit it at the end 829 // of the file. 830 llvm::DenseMap<const char*, GlobalDecl>::iterator DDI = 831 DeferredDecls.find(MangledName); 832 if (DDI != DeferredDecls.end()) { 833 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 834 // list, and remove it from DeferredDecls (since we don't need it anymore). 835 DeferredDeclsToEmit.push_back(DDI->second); 836 DeferredDecls.erase(DDI); 837 } 838 839 llvm::GlobalVariable *GV = 840 new llvm::GlobalVariable(getModule(), Ty->getElementType(), false, 841 llvm::GlobalValue::ExternalLinkage, 842 0, "", 0, 843 false, Ty->getAddressSpace()); 844 GV->setName(MangledName); 845 846 // Handle things which are present even on external declarations. 847 if (D) { 848 // FIXME: This code is overly simple and should be merged with other global 849 // handling. 850 GV->setConstant(DeclIsConstantGlobal(Context, D)); 851 852 // FIXME: Merge with other attribute handling code. 853 if (D->getStorageClass() == VarDecl::PrivateExtern) 854 GV->setVisibility(llvm::GlobalValue::HiddenVisibility); 855 856 if (D->hasAttr<WeakAttr>() || 857 D->hasAttr<WeakImportAttr>()) 858 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage); 859 860 GV->setThreadLocal(D->isThreadSpecified()); 861 } 862 863 return Entry = GV; 864} 865 866 867/// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 868/// given global variable. If Ty is non-null and if the global doesn't exist, 869/// then it will be greated with the specified type instead of whatever the 870/// normal requested type would be. 871llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 872 const llvm::Type *Ty) { 873 assert(D->hasGlobalStorage() && "Not a global variable"); 874 QualType ASTTy = D->getType(); 875 if (Ty == 0) 876 Ty = getTypes().ConvertTypeForMem(ASTTy); 877 878 const llvm::PointerType *PTy = 879 llvm::PointerType::get(Ty, ASTTy.getAddressSpace()); 880 return GetOrCreateLLVMGlobal(getMangledName(D), PTy, D); 881} 882 883/// CreateRuntimeVariable - Create a new runtime global variable with the 884/// specified type and name. 885llvm::Constant * 886CodeGenModule::CreateRuntimeVariable(const llvm::Type *Ty, 887 const char *Name) { 888 // Convert Name to be a uniqued string from the IdentifierInfo table. 889 Name = getContext().Idents.get(Name).getNameStart(); 890 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), 0); 891} 892 893void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 894 assert(!D->getInit() && "Cannot emit definite definitions here!"); 895 896 if (MayDeferGeneration(D)) { 897 // If we have not seen a reference to this variable yet, place it 898 // into the deferred declarations table to be emitted if needed 899 // later. 900 const char *MangledName = getMangledName(D); 901 if (GlobalDeclMap.count(MangledName) == 0) { 902 DeferredDecls[MangledName] = D; 903 return; 904 } 905 } 906 907 // The tentative definition is the only definition. 908 EmitGlobalVarDefinition(D); 909} 910 911llvm::GlobalVariable::LinkageTypes 912CodeGenModule::getVtableLinkage(const CXXRecordDecl *RD) { 913 if (RD->isInAnonymousNamespace() || !RD->hasLinkage()) 914 return llvm::GlobalVariable::InternalLinkage; 915 916 if (const CXXMethodDecl *KeyFunction 917 = RD->getASTContext().getKeyFunction(RD)) { 918 // If this class has a key function, use that to determine the linkage of 919 // the vtable. 920 const FunctionDecl *Def = 0; 921 if (KeyFunction->getBody(Def)) 922 KeyFunction = cast<CXXMethodDecl>(Def); 923 924 switch (KeyFunction->getTemplateSpecializationKind()) { 925 case TSK_Undeclared: 926 case TSK_ExplicitSpecialization: 927 if (KeyFunction->isInlined()) 928 return llvm::GlobalVariable::WeakODRLinkage; 929 930 return llvm::GlobalVariable::ExternalLinkage; 931 932 case TSK_ImplicitInstantiation: 933 case TSK_ExplicitInstantiationDefinition: 934 return llvm::GlobalVariable::WeakODRLinkage; 935 936 case TSK_ExplicitInstantiationDeclaration: 937 // FIXME: Use available_externally linkage. However, this currently 938 // breaks LLVM's build due to undefined symbols. 939 // return llvm::GlobalVariable::AvailableExternallyLinkage; 940 return llvm::GlobalVariable::WeakODRLinkage; 941 } 942 } 943 944 switch (RD->getTemplateSpecializationKind()) { 945 case TSK_Undeclared: 946 case TSK_ExplicitSpecialization: 947 case TSK_ImplicitInstantiation: 948 case TSK_ExplicitInstantiationDefinition: 949 return llvm::GlobalVariable::WeakODRLinkage; 950 951 case TSK_ExplicitInstantiationDeclaration: 952 // FIXME: Use available_externally linkage. However, this currently 953 // breaks LLVM's build due to undefined symbols. 954 // return llvm::GlobalVariable::AvailableExternallyLinkage; 955 return llvm::GlobalVariable::WeakODRLinkage; 956 } 957 958 // Silence GCC warning. 959 return llvm::GlobalVariable::WeakODRLinkage; 960} 961 962static CodeGenModule::GVALinkage 963GetLinkageForVariable(ASTContext &Context, const VarDecl *VD) { 964 // If this is a static data member, compute the kind of template 965 // specialization. Otherwise, this variable is not part of a 966 // template. 967 TemplateSpecializationKind TSK = TSK_Undeclared; 968 if (VD->isStaticDataMember()) 969 TSK = VD->getTemplateSpecializationKind(); 970 971 Linkage L = VD->getLinkage(); 972 if (L == ExternalLinkage && Context.getLangOptions().CPlusPlus && 973 VD->getType()->getLinkage() == UniqueExternalLinkage) 974 L = UniqueExternalLinkage; 975 976 switch (L) { 977 case NoLinkage: 978 case InternalLinkage: 979 case UniqueExternalLinkage: 980 return CodeGenModule::GVA_Internal; 981 982 case ExternalLinkage: 983 switch (TSK) { 984 case TSK_Undeclared: 985 case TSK_ExplicitSpecialization: 986 987 // FIXME: ExplicitInstantiationDefinition should be weak! 988 case TSK_ExplicitInstantiationDefinition: 989 return CodeGenModule::GVA_StrongExternal; 990 991 case TSK_ExplicitInstantiationDeclaration: 992 llvm_unreachable("Variable should not be instantiated"); 993 // Fall through to treat this like any other instantiation. 994 995 case TSK_ImplicitInstantiation: 996 return CodeGenModule::GVA_TemplateInstantiation; 997 } 998 } 999 1000 return CodeGenModule::GVA_StrongExternal; 1001} 1002 1003CharUnits CodeGenModule::GetTargetTypeStoreSize(const llvm::Type *Ty) const { 1004 return CharUnits::fromQuantity( 1005 TheTargetData.getTypeStoreSizeInBits(Ty) / Context.getCharWidth()); 1006} 1007 1008void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) { 1009 llvm::Constant *Init = 0; 1010 QualType ASTTy = D->getType(); 1011 bool NonConstInit = false; 1012 1013 const Expr *InitExpr = D->getAnyInitializer(); 1014 1015 if (!InitExpr) { 1016 // This is a tentative definition; tentative definitions are 1017 // implicitly initialized with { 0 }. 1018 // 1019 // Note that tentative definitions are only emitted at the end of 1020 // a translation unit, so they should never have incomplete 1021 // type. In addition, EmitTentativeDefinition makes sure that we 1022 // never attempt to emit a tentative definition if a real one 1023 // exists. A use may still exists, however, so we still may need 1024 // to do a RAUW. 1025 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 1026 Init = EmitNullConstant(D->getType()); 1027 } else { 1028 Init = EmitConstantExpr(InitExpr, D->getType()); 1029 1030 if (!Init) { 1031 QualType T = InitExpr->getType(); 1032 if (getLangOptions().CPlusPlus) { 1033 EmitCXXGlobalVarDeclInitFunc(D); 1034 Init = EmitNullConstant(T); 1035 NonConstInit = true; 1036 } else { 1037 ErrorUnsupported(D, "static initializer"); 1038 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 1039 } 1040 } 1041 } 1042 1043 const llvm::Type* InitType = Init->getType(); 1044 llvm::Constant *Entry = GetAddrOfGlobalVar(D, InitType); 1045 1046 // Strip off a bitcast if we got one back. 1047 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1048 assert(CE->getOpcode() == llvm::Instruction::BitCast || 1049 // all zero index gep. 1050 CE->getOpcode() == llvm::Instruction::GetElementPtr); 1051 Entry = CE->getOperand(0); 1052 } 1053 1054 // Entry is now either a Function or GlobalVariable. 1055 llvm::GlobalVariable *GV = dyn_cast<llvm::GlobalVariable>(Entry); 1056 1057 // We have a definition after a declaration with the wrong type. 1058 // We must make a new GlobalVariable* and update everything that used OldGV 1059 // (a declaration or tentative definition) with the new GlobalVariable* 1060 // (which will be a definition). 1061 // 1062 // This happens if there is a prototype for a global (e.g. 1063 // "extern int x[];") and then a definition of a different type (e.g. 1064 // "int x[10];"). This also happens when an initializer has a different type 1065 // from the type of the global (this happens with unions). 1066 if (GV == 0 || 1067 GV->getType()->getElementType() != InitType || 1068 GV->getType()->getAddressSpace() != ASTTy.getAddressSpace()) { 1069 1070 // Remove the old entry from GlobalDeclMap so that we'll create a new one. 1071 GlobalDeclMap.erase(getMangledName(D)); 1072 1073 // Make a new global with the correct type, this is now guaranteed to work. 1074 GV = cast<llvm::GlobalVariable>(GetAddrOfGlobalVar(D, InitType)); 1075 GV->takeName(cast<llvm::GlobalValue>(Entry)); 1076 1077 // Replace all uses of the old global with the new global 1078 llvm::Constant *NewPtrForOldDecl = 1079 llvm::ConstantExpr::getBitCast(GV, Entry->getType()); 1080 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1081 1082 // Erase the old global, since it is no longer used. 1083 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 1084 } 1085 1086 if (const AnnotateAttr *AA = D->getAttr<AnnotateAttr>()) { 1087 SourceManager &SM = Context.getSourceManager(); 1088 AddAnnotation(EmitAnnotateAttr(GV, AA, 1089 SM.getInstantiationLineNumber(D->getLocation()))); 1090 } 1091 1092 GV->setInitializer(Init); 1093 1094 // If it is safe to mark the global 'constant', do so now. 1095 GV->setConstant(false); 1096 if (!NonConstInit && DeclIsConstantGlobal(Context, D)) 1097 GV->setConstant(true); 1098 1099 GV->setAlignment(getContext().getDeclAlign(D).getQuantity()); 1100 1101 // Set the llvm linkage type as appropriate. 1102 GVALinkage Linkage = GetLinkageForVariable(getContext(), D); 1103 if (Linkage == GVA_Internal) 1104 GV->setLinkage(llvm::Function::InternalLinkage); 1105 else if (D->hasAttr<DLLImportAttr>()) 1106 GV->setLinkage(llvm::Function::DLLImportLinkage); 1107 else if (D->hasAttr<DLLExportAttr>()) 1108 GV->setLinkage(llvm::Function::DLLExportLinkage); 1109 else if (D->hasAttr<WeakAttr>()) { 1110 if (GV->isConstant()) 1111 GV->setLinkage(llvm::GlobalVariable::WeakODRLinkage); 1112 else 1113 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 1114 } else if (Linkage == GVA_TemplateInstantiation) 1115 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 1116 else if (!getLangOptions().CPlusPlus && !CodeGenOpts.NoCommon && 1117 !D->hasExternalStorage() && !D->getInit() && 1118 !D->getAttr<SectionAttr>()) { 1119 GV->setLinkage(llvm::GlobalVariable::CommonLinkage); 1120 // common vars aren't constant even if declared const. 1121 GV->setConstant(false); 1122 } else 1123 GV->setLinkage(llvm::GlobalVariable::ExternalLinkage); 1124 1125 SetCommonAttributes(D, GV); 1126 1127 // Emit global variable debug information. 1128 if (CGDebugInfo *DI = getDebugInfo()) { 1129 DI->setLocation(D->getLocation()); 1130 DI->EmitGlobalVariable(GV, D); 1131 } 1132} 1133 1134/// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 1135/// implement a function with no prototype, e.g. "int foo() {}". If there are 1136/// existing call uses of the old function in the module, this adjusts them to 1137/// call the new function directly. 1138/// 1139/// This is not just a cleanup: the always_inline pass requires direct calls to 1140/// functions to be able to inline them. If there is a bitcast in the way, it 1141/// won't inline them. Instcombine normally deletes these calls, but it isn't 1142/// run at -O0. 1143static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 1144 llvm::Function *NewFn) { 1145 // If we're redefining a global as a function, don't transform it. 1146 llvm::Function *OldFn = dyn_cast<llvm::Function>(Old); 1147 if (OldFn == 0) return; 1148 1149 const llvm::Type *NewRetTy = NewFn->getReturnType(); 1150 llvm::SmallVector<llvm::Value*, 4> ArgList; 1151 1152 for (llvm::Value::use_iterator UI = OldFn->use_begin(), E = OldFn->use_end(); 1153 UI != E; ) { 1154 // TODO: Do invokes ever occur in C code? If so, we should handle them too. 1155 unsigned OpNo = UI.getOperandNo(); 1156 llvm::CallInst *CI = dyn_cast<llvm::CallInst>(*UI++); 1157 if (!CI || OpNo != 0) continue; 1158 1159 // If the return types don't match exactly, and if the call isn't dead, then 1160 // we can't transform this call. 1161 if (CI->getType() != NewRetTy && !CI->use_empty()) 1162 continue; 1163 1164 // If the function was passed too few arguments, don't transform. If extra 1165 // arguments were passed, we silently drop them. If any of the types 1166 // mismatch, we don't transform. 1167 unsigned ArgNo = 0; 1168 bool DontTransform = false; 1169 for (llvm::Function::arg_iterator AI = NewFn->arg_begin(), 1170 E = NewFn->arg_end(); AI != E; ++AI, ++ArgNo) { 1171 if (CI->getNumOperands()-1 == ArgNo || 1172 CI->getOperand(ArgNo+1)->getType() != AI->getType()) { 1173 DontTransform = true; 1174 break; 1175 } 1176 } 1177 if (DontTransform) 1178 continue; 1179 1180 // Okay, we can transform this. Create the new call instruction and copy 1181 // over the required information. 1182 ArgList.append(CI->op_begin()+1, CI->op_begin()+1+ArgNo); 1183 llvm::CallInst *NewCall = llvm::CallInst::Create(NewFn, ArgList.begin(), 1184 ArgList.end(), "", CI); 1185 ArgList.clear(); 1186 if (!NewCall->getType()->isVoidTy()) 1187 NewCall->takeName(CI); 1188 NewCall->setAttributes(CI->getAttributes()); 1189 NewCall->setCallingConv(CI->getCallingConv()); 1190 1191 // Finally, remove the old call, replacing any uses with the new one. 1192 if (!CI->use_empty()) 1193 CI->replaceAllUsesWith(NewCall); 1194 1195 // Copy any custom metadata attached with CI. 1196 if (llvm::MDNode *DbgNode = CI->getMetadata("dbg")) 1197 NewCall->setMetadata("dbg", DbgNode); 1198 CI->eraseFromParent(); 1199 } 1200} 1201 1202 1203void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD) { 1204 const FunctionDecl *D = cast<FunctionDecl>(GD.getDecl()); 1205 const llvm::FunctionType *Ty = getTypes().GetFunctionType(GD); 1206 getMangleContext().mangleInitDiscriminator(); 1207 // Get or create the prototype for the function. 1208 llvm::Constant *Entry = GetAddrOfFunction(GD, Ty); 1209 1210 // Strip off a bitcast if we got one back. 1211 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) { 1212 assert(CE->getOpcode() == llvm::Instruction::BitCast); 1213 Entry = CE->getOperand(0); 1214 } 1215 1216 1217 if (cast<llvm::GlobalValue>(Entry)->getType()->getElementType() != Ty) { 1218 llvm::GlobalValue *OldFn = cast<llvm::GlobalValue>(Entry); 1219 1220 // If the types mismatch then we have to rewrite the definition. 1221 assert(OldFn->isDeclaration() && 1222 "Shouldn't replace non-declaration"); 1223 1224 // F is the Function* for the one with the wrong type, we must make a new 1225 // Function* and update everything that used F (a declaration) with the new 1226 // Function* (which will be a definition). 1227 // 1228 // This happens if there is a prototype for a function 1229 // (e.g. "int f()") and then a definition of a different type 1230 // (e.g. "int f(int x)"). Start by making a new function of the 1231 // correct type, RAUW, then steal the name. 1232 GlobalDeclMap.erase(getMangledName(D)); 1233 llvm::Function *NewFn = cast<llvm::Function>(GetAddrOfFunction(GD, Ty)); 1234 NewFn->takeName(OldFn); 1235 1236 // If this is an implementation of a function without a prototype, try to 1237 // replace any existing uses of the function (which may be calls) with uses 1238 // of the new function 1239 if (D->getType()->isFunctionNoProtoType()) { 1240 ReplaceUsesOfNonProtoTypeWithRealFunction(OldFn, NewFn); 1241 OldFn->removeDeadConstantUsers(); 1242 } 1243 1244 // Replace uses of F with the Function we will endow with a body. 1245 if (!Entry->use_empty()) { 1246 llvm::Constant *NewPtrForOldDecl = 1247 llvm::ConstantExpr::getBitCast(NewFn, Entry->getType()); 1248 Entry->replaceAllUsesWith(NewPtrForOldDecl); 1249 } 1250 1251 // Ok, delete the old function now, which is dead. 1252 OldFn->eraseFromParent(); 1253 1254 Entry = NewFn; 1255 } 1256 1257 llvm::Function *Fn = cast<llvm::Function>(Entry); 1258 1259 CodeGenFunction(*this).GenerateCode(D, Fn); 1260 1261 SetFunctionDefinitionAttributes(D, Fn); 1262 SetLLVMFunctionAttributesForDefinition(D, Fn); 1263 1264 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 1265 AddGlobalCtor(Fn, CA->getPriority()); 1266 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 1267 AddGlobalDtor(Fn, DA->getPriority()); 1268} 1269 1270void CodeGenModule::EmitAliasDefinition(const ValueDecl *D) { 1271 const AliasAttr *AA = D->getAttr<AliasAttr>(); 1272 assert(AA && "Not an alias?"); 1273 1274 const llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 1275 1276 // Unique the name through the identifier table. 1277 const char *AliaseeName = 1278 getContext().Idents.get(AA->getAliasee()).getNameStart(); 1279 1280 // Create a reference to the named value. This ensures that it is emitted 1281 // if a deferred decl. 1282 llvm::Constant *Aliasee; 1283 if (isa<llvm::FunctionType>(DeclTy)) 1284 Aliasee = GetOrCreateLLVMFunction(AliaseeName, DeclTy, GlobalDecl()); 1285 else 1286 Aliasee = GetOrCreateLLVMGlobal(AliaseeName, 1287 llvm::PointerType::getUnqual(DeclTy), 0); 1288 1289 // Create the new alias itself, but don't set a name yet. 1290 llvm::GlobalValue *GA = 1291 new llvm::GlobalAlias(Aliasee->getType(), 1292 llvm::Function::ExternalLinkage, 1293 "", Aliasee, &getModule()); 1294 1295 // See if there is already something with the alias' name in the module. 1296 const char *MangledName = getMangledName(D); 1297 llvm::GlobalValue *&Entry = GlobalDeclMap[MangledName]; 1298 1299 if (Entry && !Entry->isDeclaration()) { 1300 // If there is a definition in the module, then it wins over the alias. 1301 // This is dubious, but allow it to be safe. Just ignore the alias. 1302 GA->eraseFromParent(); 1303 return; 1304 } 1305 1306 if (Entry) { 1307 // If there is a declaration in the module, then we had an extern followed 1308 // by the alias, as in: 1309 // extern int test6(); 1310 // ... 1311 // int test6() __attribute__((alias("test7"))); 1312 // 1313 // Remove it and replace uses of it with the alias. 1314 1315 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA, 1316 Entry->getType())); 1317 Entry->eraseFromParent(); 1318 } 1319 1320 // Now we know that there is no conflict, set the name. 1321 Entry = GA; 1322 GA->setName(MangledName); 1323 1324 // Set attributes which are particular to an alias; this is a 1325 // specialization of the attributes which may be set on a global 1326 // variable/function. 1327 if (D->hasAttr<DLLExportAttr>()) { 1328 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1329 // The dllexport attribute is ignored for undefined symbols. 1330 if (FD->getBody()) 1331 GA->setLinkage(llvm::Function::DLLExportLinkage); 1332 } else { 1333 GA->setLinkage(llvm::Function::DLLExportLinkage); 1334 } 1335 } else if (D->hasAttr<WeakAttr>() || 1336 D->hasAttr<WeakRefAttr>() || 1337 D->hasAttr<WeakImportAttr>()) { 1338 GA->setLinkage(llvm::Function::WeakAnyLinkage); 1339 } 1340 1341 SetCommonAttributes(D, GA); 1342} 1343 1344/// getBuiltinLibFunction - Given a builtin id for a function like 1345/// "__builtin_fabsf", return a Function* for "fabsf". 1346llvm::Value *CodeGenModule::getBuiltinLibFunction(const FunctionDecl *FD, 1347 unsigned BuiltinID) { 1348 assert((Context.BuiltinInfo.isLibFunction(BuiltinID) || 1349 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) && 1350 "isn't a lib fn"); 1351 1352 // Get the name, skip over the __builtin_ prefix (if necessary). 1353 const char *Name = Context.BuiltinInfo.GetName(BuiltinID); 1354 if (Context.BuiltinInfo.isLibFunction(BuiltinID)) 1355 Name += 10; 1356 1357 const llvm::FunctionType *Ty = 1358 cast<llvm::FunctionType>(getTypes().ConvertType(FD->getType())); 1359 1360 // Unique the name through the identifier table. 1361 Name = getContext().Idents.get(Name).getNameStart(); 1362 return GetOrCreateLLVMFunction(Name, Ty, GlobalDecl(FD)); 1363} 1364 1365llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,const llvm::Type **Tys, 1366 unsigned NumTys) { 1367 return llvm::Intrinsic::getDeclaration(&getModule(), 1368 (llvm::Intrinsic::ID)IID, Tys, NumTys); 1369} 1370 1371llvm::Function *CodeGenModule::getMemCpyFn() { 1372 if (MemCpyFn) return MemCpyFn; 1373 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1374 return MemCpyFn = getIntrinsic(llvm::Intrinsic::memcpy, &IntPtr, 1); 1375} 1376 1377llvm::Function *CodeGenModule::getMemMoveFn() { 1378 if (MemMoveFn) return MemMoveFn; 1379 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1380 return MemMoveFn = getIntrinsic(llvm::Intrinsic::memmove, &IntPtr, 1); 1381} 1382 1383llvm::Function *CodeGenModule::getMemSetFn() { 1384 if (MemSetFn) return MemSetFn; 1385 const llvm::Type *IntPtr = TheTargetData.getIntPtrType(VMContext); 1386 return MemSetFn = getIntrinsic(llvm::Intrinsic::memset, &IntPtr, 1); 1387} 1388 1389static llvm::StringMapEntry<llvm::Constant*> & 1390GetConstantCFStringEntry(llvm::StringMap<llvm::Constant*> &Map, 1391 const StringLiteral *Literal, 1392 bool TargetIsLSB, 1393 bool &IsUTF16, 1394 unsigned &StringLength) { 1395 unsigned NumBytes = Literal->getByteLength(); 1396 1397 // Check for simple case. 1398 if (!Literal->containsNonAsciiOrNull()) { 1399 StringLength = NumBytes; 1400 return Map.GetOrCreateValue(llvm::StringRef(Literal->getStrData(), 1401 StringLength)); 1402 } 1403 1404 // Otherwise, convert the UTF8 literals into a byte string. 1405 llvm::SmallVector<UTF16, 128> ToBuf(NumBytes); 1406 const UTF8 *FromPtr = (UTF8 *)Literal->getStrData(); 1407 UTF16 *ToPtr = &ToBuf[0]; 1408 1409 ConversionResult Result = ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, 1410 &ToPtr, ToPtr + NumBytes, 1411 strictConversion); 1412 1413 // Check for conversion failure. 1414 if (Result != conversionOK) { 1415 // FIXME: Have Sema::CheckObjCString() validate the UTF-8 string and remove 1416 // this duplicate code. 1417 assert(Result == sourceIllegal && "UTF-8 to UTF-16 conversion failed"); 1418 StringLength = NumBytes; 1419 return Map.GetOrCreateValue(llvm::StringRef(Literal->getStrData(), 1420 StringLength)); 1421 } 1422 1423 // ConvertUTF8toUTF16 returns the length in ToPtr. 1424 StringLength = ToPtr - &ToBuf[0]; 1425 1426 // Render the UTF-16 string into a byte array and convert to the target byte 1427 // order. 1428 // 1429 // FIXME: This isn't something we should need to do here. 1430 llvm::SmallString<128> AsBytes; 1431 AsBytes.reserve(StringLength * 2); 1432 for (unsigned i = 0; i != StringLength; ++i) { 1433 unsigned short Val = ToBuf[i]; 1434 if (TargetIsLSB) { 1435 AsBytes.push_back(Val & 0xFF); 1436 AsBytes.push_back(Val >> 8); 1437 } else { 1438 AsBytes.push_back(Val >> 8); 1439 AsBytes.push_back(Val & 0xFF); 1440 } 1441 } 1442 // Append one extra null character, the second is automatically added by our 1443 // caller. 1444 AsBytes.push_back(0); 1445 1446 IsUTF16 = true; 1447 return Map.GetOrCreateValue(llvm::StringRef(AsBytes.data(), AsBytes.size())); 1448} 1449 1450llvm::Constant * 1451CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 1452 unsigned StringLength = 0; 1453 bool isUTF16 = false; 1454 llvm::StringMapEntry<llvm::Constant*> &Entry = 1455 GetConstantCFStringEntry(CFConstantStringMap, Literal, 1456 getTargetData().isLittleEndian(), 1457 isUTF16, StringLength); 1458 1459 if (llvm::Constant *C = Entry.getValue()) 1460 return C; 1461 1462 llvm::Constant *Zero = 1463 llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext)); 1464 llvm::Constant *Zeros[] = { Zero, Zero }; 1465 1466 // If we don't already have it, get __CFConstantStringClassReference. 1467 if (!CFConstantStringClassRef) { 1468 const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 1469 Ty = llvm::ArrayType::get(Ty, 0); 1470 llvm::Constant *GV = CreateRuntimeVariable(Ty, 1471 "__CFConstantStringClassReference"); 1472 // Decay array -> ptr 1473 CFConstantStringClassRef = 1474 llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1475 } 1476 1477 QualType CFTy = getContext().getCFConstantStringType(); 1478 1479 const llvm::StructType *STy = 1480 cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 1481 1482 std::vector<llvm::Constant*> Fields(4); 1483 1484 // Class pointer. 1485 Fields[0] = CFConstantStringClassRef; 1486 1487 // Flags. 1488 const llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy); 1489 Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0) : 1490 llvm::ConstantInt::get(Ty, 0x07C8); 1491 1492 // String pointer. 1493 llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str()); 1494 1495 llvm::GlobalValue::LinkageTypes Linkage; 1496 bool isConstant; 1497 if (isUTF16) { 1498 // FIXME: why do utf strings get "_" labels instead of "L" labels? 1499 Linkage = llvm::GlobalValue::InternalLinkage; 1500 // Note: -fwritable-strings doesn't make unicode CFStrings writable, but 1501 // does make plain ascii ones writable. 1502 isConstant = true; 1503 } else { 1504 Linkage = llvm::GlobalValue::PrivateLinkage; 1505 isConstant = !Features.WritableStrings; 1506 } 1507 1508 llvm::GlobalVariable *GV = 1509 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C, 1510 ".str"); 1511 if (isUTF16) { 1512 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy); 1513 GV->setAlignment(Align.getQuantity()); 1514 } 1515 Fields[2] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2); 1516 1517 // String length. 1518 Ty = getTypes().ConvertType(getContext().LongTy); 1519 Fields[3] = llvm::ConstantInt::get(Ty, StringLength); 1520 1521 // The struct. 1522 C = llvm::ConstantStruct::get(STy, Fields); 1523 GV = new llvm::GlobalVariable(getModule(), C->getType(), true, 1524 llvm::GlobalVariable::PrivateLinkage, C, 1525 "_unnamed_cfstring_"); 1526 if (const char *Sect = getContext().Target.getCFStringSection()) 1527 GV->setSection(Sect); 1528 Entry.setValue(GV); 1529 1530 return GV; 1531} 1532 1533/// GetStringForStringLiteral - Return the appropriate bytes for a 1534/// string literal, properly padded to match the literal type. 1535std::string CodeGenModule::GetStringForStringLiteral(const StringLiteral *E) { 1536 const char *StrData = E->getStrData(); 1537 unsigned Len = E->getByteLength(); 1538 1539 const ConstantArrayType *CAT = 1540 getContext().getAsConstantArrayType(E->getType()); 1541 assert(CAT && "String isn't pointer or array!"); 1542 1543 // Resize the string to the right size. 1544 std::string Str(StrData, StrData+Len); 1545 uint64_t RealLen = CAT->getSize().getZExtValue(); 1546 1547 if (E->isWide()) 1548 RealLen *= getContext().Target.getWCharWidth()/8; 1549 1550 Str.resize(RealLen, '\0'); 1551 1552 return Str; 1553} 1554 1555/// GetAddrOfConstantStringFromLiteral - Return a pointer to a 1556/// constant array for the given string literal. 1557llvm::Constant * 1558CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) { 1559 // FIXME: This can be more efficient. 1560 // FIXME: We shouldn't need to bitcast the constant in the wide string case. 1561 llvm::Constant *C = GetAddrOfConstantString(GetStringForStringLiteral(S)); 1562 if (S->isWide()) { 1563 llvm::Type *DestTy = 1564 llvm::PointerType::getUnqual(getTypes().ConvertType(S->getType())); 1565 C = llvm::ConstantExpr::getBitCast(C, DestTy); 1566 } 1567 return C; 1568} 1569 1570/// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 1571/// array for the given ObjCEncodeExpr node. 1572llvm::Constant * 1573CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 1574 std::string Str; 1575 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 1576 1577 return GetAddrOfConstantCString(Str); 1578} 1579 1580 1581/// GenerateWritableString -- Creates storage for a string literal. 1582static llvm::Constant *GenerateStringLiteral(const std::string &str, 1583 bool constant, 1584 CodeGenModule &CGM, 1585 const char *GlobalName) { 1586 // Create Constant for this string literal. Don't add a '\0'. 1587 llvm::Constant *C = 1588 llvm::ConstantArray::get(CGM.getLLVMContext(), str, false); 1589 1590 // Create a global variable for this string 1591 return new llvm::GlobalVariable(CGM.getModule(), C->getType(), constant, 1592 llvm::GlobalValue::PrivateLinkage, 1593 C, GlobalName); 1594} 1595 1596/// GetAddrOfConstantString - Returns a pointer to a character array 1597/// containing the literal. This contents are exactly that of the 1598/// given string, i.e. it will not be null terminated automatically; 1599/// see GetAddrOfConstantCString. Note that whether the result is 1600/// actually a pointer to an LLVM constant depends on 1601/// Feature.WriteableStrings. 1602/// 1603/// The result has pointer to array type. 1604llvm::Constant *CodeGenModule::GetAddrOfConstantString(const std::string &str, 1605 const char *GlobalName) { 1606 bool IsConstant = !Features.WritableStrings; 1607 1608 // Get the default prefix if a name wasn't specified. 1609 if (!GlobalName) 1610 GlobalName = ".str"; 1611 1612 // Don't share any string literals if strings aren't constant. 1613 if (!IsConstant) 1614 return GenerateStringLiteral(str, false, *this, GlobalName); 1615 1616 llvm::StringMapEntry<llvm::Constant *> &Entry = 1617 ConstantStringMap.GetOrCreateValue(&str[0], &str[str.length()]); 1618 1619 if (Entry.getValue()) 1620 return Entry.getValue(); 1621 1622 // Create a global variable for this. 1623 llvm::Constant *C = GenerateStringLiteral(str, true, *this, GlobalName); 1624 Entry.setValue(C); 1625 return C; 1626} 1627 1628/// GetAddrOfConstantCString - Returns a pointer to a character 1629/// array containing the literal and a terminating '\-' 1630/// character. The result has pointer to array type. 1631llvm::Constant *CodeGenModule::GetAddrOfConstantCString(const std::string &str, 1632 const char *GlobalName){ 1633 return GetAddrOfConstantString(str + '\0', GlobalName); 1634} 1635 1636/// EmitObjCPropertyImplementations - Emit information for synthesized 1637/// properties for an implementation. 1638void CodeGenModule::EmitObjCPropertyImplementations(const 1639 ObjCImplementationDecl *D) { 1640 for (ObjCImplementationDecl::propimpl_iterator 1641 i = D->propimpl_begin(), e = D->propimpl_end(); i != e; ++i) { 1642 ObjCPropertyImplDecl *PID = *i; 1643 1644 // Dynamic is just for type-checking. 1645 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 1646 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 1647 1648 // Determine which methods need to be implemented, some may have 1649 // been overridden. Note that ::isSynthesized is not the method 1650 // we want, that just indicates if the decl came from a 1651 // property. What we want to know is if the method is defined in 1652 // this implementation. 1653 if (!D->getInstanceMethod(PD->getGetterName())) 1654 CodeGenFunction(*this).GenerateObjCGetter( 1655 const_cast<ObjCImplementationDecl *>(D), PID); 1656 if (!PD->isReadOnly() && 1657 !D->getInstanceMethod(PD->getSetterName())) 1658 CodeGenFunction(*this).GenerateObjCSetter( 1659 const_cast<ObjCImplementationDecl *>(D), PID); 1660 } 1661 } 1662} 1663 1664/// EmitNamespace - Emit all declarations in a namespace. 1665void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) { 1666 for (RecordDecl::decl_iterator I = ND->decls_begin(), E = ND->decls_end(); 1667 I != E; ++I) 1668 EmitTopLevelDecl(*I); 1669} 1670 1671// EmitLinkageSpec - Emit all declarations in a linkage spec. 1672void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 1673 if (LSD->getLanguage() != LinkageSpecDecl::lang_c && 1674 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) { 1675 ErrorUnsupported(LSD, "linkage spec"); 1676 return; 1677 } 1678 1679 for (RecordDecl::decl_iterator I = LSD->decls_begin(), E = LSD->decls_end(); 1680 I != E; ++I) 1681 EmitTopLevelDecl(*I); 1682} 1683 1684/// EmitTopLevelDecl - Emit code for a single top level declaration. 1685void CodeGenModule::EmitTopLevelDecl(Decl *D) { 1686 // If an error has occurred, stop code generation, but continue 1687 // parsing and semantic analysis (to ensure all warnings and errors 1688 // are emitted). 1689 if (Diags.hasErrorOccurred()) 1690 return; 1691 1692 // Ignore dependent declarations. 1693 if (D->getDeclContext() && D->getDeclContext()->isDependentContext()) 1694 return; 1695 1696 switch (D->getKind()) { 1697 case Decl::CXXConversion: 1698 case Decl::CXXMethod: 1699 case Decl::Function: 1700 // Skip function templates 1701 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate()) 1702 return; 1703 1704 EmitGlobal(cast<FunctionDecl>(D)); 1705 break; 1706 1707 case Decl::Var: 1708 EmitGlobal(cast<VarDecl>(D)); 1709 break; 1710 1711 // C++ Decls 1712 case Decl::Namespace: 1713 EmitNamespace(cast<NamespaceDecl>(D)); 1714 break; 1715 // No code generation needed. 1716 case Decl::UsingShadow: 1717 case Decl::Using: 1718 case Decl::UsingDirective: 1719 case Decl::ClassTemplate: 1720 case Decl::FunctionTemplate: 1721 case Decl::NamespaceAlias: 1722 break; 1723 case Decl::CXXConstructor: 1724 // Skip function templates 1725 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate()) 1726 return; 1727 1728 EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 1729 break; 1730 case Decl::CXXDestructor: 1731 EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 1732 break; 1733 1734 case Decl::StaticAssert: 1735 // Nothing to do. 1736 break; 1737 1738 // Objective-C Decls 1739 1740 // Forward declarations, no (immediate) code generation. 1741 case Decl::ObjCClass: 1742 case Decl::ObjCForwardProtocol: 1743 case Decl::ObjCCategory: 1744 case Decl::ObjCInterface: 1745 break; 1746 1747 case Decl::ObjCProtocol: 1748 Runtime->GenerateProtocol(cast<ObjCProtocolDecl>(D)); 1749 break; 1750 1751 case Decl::ObjCCategoryImpl: 1752 // Categories have properties but don't support synthesize so we 1753 // can ignore them here. 1754 Runtime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 1755 break; 1756 1757 case Decl::ObjCImplementation: { 1758 ObjCImplementationDecl *OMD = cast<ObjCImplementationDecl>(D); 1759 EmitObjCPropertyImplementations(OMD); 1760 Runtime->GenerateClass(OMD); 1761 break; 1762 } 1763 case Decl::ObjCMethod: { 1764 ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(D); 1765 // If this is not a prototype, emit the body. 1766 if (OMD->getBody()) 1767 CodeGenFunction(*this).GenerateObjCMethod(OMD); 1768 break; 1769 } 1770 case Decl::ObjCCompatibleAlias: 1771 // compatibility-alias is a directive and has no code gen. 1772 break; 1773 1774 case Decl::LinkageSpec: 1775 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 1776 break; 1777 1778 case Decl::FileScopeAsm: { 1779 FileScopeAsmDecl *AD = cast<FileScopeAsmDecl>(D); 1780 llvm::StringRef AsmString = AD->getAsmString()->getString(); 1781 1782 const std::string &S = getModule().getModuleInlineAsm(); 1783 if (S.empty()) 1784 getModule().setModuleInlineAsm(AsmString); 1785 else 1786 getModule().setModuleInlineAsm(S + '\n' + AsmString.str()); 1787 break; 1788 } 1789 1790 default: 1791 // Make sure we handled everything we should, every other kind is a 1792 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 1793 // function. Need to recode Decl::Kind to do that easily. 1794 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 1795 } 1796} 1797